This invention relates to a case for holding a magnetic tape cassette.
As illustrated in FIG. 1, an ordinary magnetic tape cassette 2 is commonly placed in a case 4, while not in use, for its protection as well as for convenience of handling. An additional function of the case is to lock the supply and takeup reels or hubs 6 of the cassette 2 lest a length of magnetic tape on the both hubs move from one hub to the other while being contained in the case. To that end, the case 4 is formed with flat locking projections or tabs 8 upright at points of the bottom wall of the case where they meet the hubs 6 of the magnetic tape cassette 2. (Refer also to FIG. 2) The upright tabs 8 are so shaped and located as to enter among the inwardly protruding spokes 10 of the hubs to lock them from unwanted rotation.
Generally, the case 4 comprises a main body 4a having the locking tabs 8 and a turnable lid 4b hingedly secured to the body 4a. The turnable lid 4b has a pocket 4c in which it receives the magnetic tape cassette 2 and pivots in the direction of the arrow A onto the body to the closed state shown in FIG. 3. The magnetic tape cassette 2 is contained in the manner, as indicated in FIG. 3, resting at one end of steps 5' of stepped support ribs 5 formed on the inner end wall surface of the case body 4a. The upright tabs 8 remain engaged with the spokes 10 of the hubs 6 as shown in FIG. 1.
Actually, it is not uncommon, as FIGS. 4 to 6 indicate, that the tip of any of the inwardly protruding spokes 10 of the hubs 6 comes gradually into contact, as at 11' and 11", with the edge 9 of any of the tabs 8, instead of properly engaging the latter, and is guided by the edge 9 into the encased state. This means that the magnetic tape cassette is forced into the case through pressure contact with either or both of the upright tabs 8 and the stepped support rib or ribs 5. Understandably, the case 4 will become too tight to open, resulting in a breakage of the case and even the cassette hub or hubs themselves.
The present invention has for its object the provision of a novel case for holding a magnetic tape cassette, with upright tabs uniquely shaped to solve the aforementioned problems of the conventional cases.